The Scientific Committee on Consumer Safety (SCCS) Opinion on fragrance allergy in consumers has confirmed that fragrance allergens identified by the Scientific Committee on Cosmetic Products and Non-food products (SCCNFP) intended for consumers in 1999 are still relevant fragrance allergens for consumers who use cosmetic products. IFRA has released a statement on the matter.

Based on clinical experience, the most recent SCCNFP Opinion revealed that 82 substances can be classified as established contact allergens in humans, of which 54 are single chemicals and 28 are natural extracts. Of these, 12 chemicals and eight natural extracts were found to pose a high risk of sensitization to the consumer, considering the high number of reported cases. Thirteen of the allergenic fragrance substances, which are listed in the Opinion, have been frequently reported as well-recognized contact allergens in consumers, while 11 others aren't as well-documented.

One ingredient in particular stood out, hydroxyisohexyl 3-cyclohexene carboxaldehyde (HICC), since it had more than 1,500 reported allergenic cases since the Opinion published in 1999. As a result of the public consultation on perfumery materials, which ended on Jan. 27, 2007, there were further requests and information on important and/or frequently used allergens other than those proposed for regulation, such as farnesol, citral, linalool and hydroxyisohexyl-3-cyclohexenecarboxaldehyde. These substances were not part of the consultation, but the Opinion said they all belong to the 26 fragrance substances which should be labeled when present in cosmetic products under certain conditions.

Perfumes and deodorants are the most frequent sources of sensitization to fragrance ingredients in women, the Opinion indicated, while aftershave products and deodorants impact men. Eczema may appear or worsen by contact with other fragranced products such as cosmetics, toiletries, household products, industrial contacts and flavorings. The Opinion also said that popular fine fragrances as well as toilet soaps, shampoos, lotions, deodorants and aftershaves have been shown to provoke allergic contact dermatitis in patients when used for patch testing.

Commercially available fragrance formulae and dilutions of individual fragrance allergens were potent elicitors of allergic contact dermatitis under simulated use conditions. More recently, deodorants spiked with the fragrance allergens cinnamal, hydroxycitronellal and HICC, respectively, in realistic in-use concentrations were shown to elicit allergic contact dermatitis in 89–100% of the fragrance allergic individuals tested. In 87.5% of HICC sensitized individuals, the use of a cream (and in 82.8% the use of an ethanol solution) spiked with HICC provoked dermatitis .

Based on the clinical data, oxidized limonene and oxidized linalool are allergens of high concern, which pose a high risk of sensitization to the consumer. For these substances, the Opinion said, the presence of the oxidized fraction represented by the peroxide content should not be higher than 10 ppm. Alternatively, the suggested general threshold dose/area of 0.8 µg/cm2 (100 ppm in cosmetic products) could be applicable to the total oxidized fraction, (not only peroxides but also secondary oxidation products such as aldehydes and epoxides).

The dose elicitation studies available indicate that a general level of exposure of up to 0.8 µg/cm2 (0.01%) may be tolerated by most consumers with contact allergy to fragrance allergens. The SCCS considers that this level of exposure could be efficient in limiting elicitation unless there is substance specific data, either experimental or clinical, to the contrary.

The Opinion states that it was not possible to provide a safe threshold for natural extracts of concern, as no specific investigations exist and the model providing the general threshold (0.01%) has been based on individual chemicals only. However, the SCCS considers that the maximum use concentration applies to the above identified fragrance allergens also when present in the natural extract. This will also reduce the risk of sensitization and elicitation from natural extracts.

In the case of hydroxyisohexyl 3-cyclohexene carboxaldehyde, in 2003 the SCCP suggested that levels of up to 200 ppm would be tolerated by the majority of sensitized individuals. Recent voluntary restrictions (recommendations to lower use concentrations, at least for some product types, to the level recommended by the SCCS in 2003) are not reflected in available evidence and are considered insufficient. The SCCS considers that the number of cases of HICC allergy documented over the last decade is exceptionally high and that continued exposure to HICC by the consumer is not considered safe, even at concentrations as low as 200 ppm. Therefore, HICC should not be used in consumer products in order to prevent further cases of contact allergy to HICC and to limit the consequences to those who already have become sensitized.

The SCCS also posted its opinion that the presence of the two constituents, chloroatranol and atranol, in cosmetic products are not safe.